1. Field of the Invention
The present invention relates to a method for controlling a freezing burst prevention operation of a hot water supply and heating system associated with a heat pump.
2. Discussion of the Related Art
A hot water supply and heating apparatus associated with a heat pump is an apparatus which is combined with a heat pump cycle and a hot water circulation unit and performs heat-exchange between water and refrigerant discharged from a compressor which constitutes a heat pump refrigerant circuit to perform a hot water supply and a floor heating.
In a conventional system, a pipe for water flowing along a closed cycle for heating is separated from that for supplying hot water, and heat exchange is performed at each different spot of the pipe on the outlet side of the compressor of the heat pump refrigerant circuit. That is, in the conventional system, a water-refrigerant heat exchanger for heating and a water-refrigerant heat exchanger for hot water supply are separate.
In the conventional system, water supplied for hot water supply performs heat-exchange with the refrigerant, while passing through the water-refrigerant heat exchanger for hot water supply, and is then directly discharged.
In the conventional hot water supply and heating apparatus associated with the heat pump, there has been no safety apparatus which prevents freezing of a water-refrigerant heat-exchanger provided in an indoor unit. The water-refrigerant heat-exchanger generally uses a plate-type heat-exchanger performing heat exchange between water and a refrigerant. However, if water flowing along the inside of the plate-type heat-exchanger is frozen, the volume of water is expanded. The plate-type heat-exchanger may be damaged due to the volume expansion occurred during the freezing process. If the plate-type heat-exchanger is damaged, water is mixed with the refrigerant and the mixture of the water and refrigerant is flowed into a component of an outdoor unit, in particular, into a compressor, thereby causing damage to the compressor.
Furthermore, the plate-type heat-exchanger is more expensive than a fin-type heat-exchanger, causing a high replacement cost when the plate-type heat-exchanger is damaged.